In recent years, various types of navigation apparatuses that receive traffic information from a Vehicle Information and Communication System (VICS: a registered trademark) via a radio wave beacon, an optical beacon or frequency modulation multiple broadcasting have been disclosed.
Also, various types of traffic information distributing apparatuses and traffic information distributing methods that distribute traffic information according to a transmission request received from a navigation apparatus installed in a vehicle have been proposed.
One example is a traffic information distributing apparatus that, in a case where a downloading request for downloading traffic information around a current position is transmitted from the navigation apparatus, reads traffic information, congestion prediction data and congestion statistical data distributed from the Vehicle Information and Communication System (VICS: a registered trademark) from a traffic information database (DB), and sends them to the navigation apparatus (see, for example, Japanese Patent Application Publication No. JP-A-2003-302229, paragraphs 0010 to 0054 and FIGS. 1 to 13).
In the navigation apparatus installed in the vehicle, the traffic information, the congestion prediction data or the like received from the Vehicle Information and Communication System (VICS: a registered trademark) and the traffic information distributing apparatus are used for searching or guiding a route to a destination.